Well I might have been a bit harsh :D
When I was consulting I tried to be better than those I'd dealt with in the past as well.
It's not so much that consultants do shoddy work, it's more that they get forced in to positions where it's impossibble to meet desirable standards and make a buck, unless you plump for repeat business through quality. That's only possible because 'your' familiarity with the client's needs and the last solution, plus a hopefuilly good relationship are allowed to count.
Doesn't matter how much effort you put in though if the client looks at each job fresh, and goes on price.
So I submit the ability to sell yourself, is way more important than anything else.